Thermal Printer

Abstract

The utility model relates to a thermal printer, including a paper bin shell, a width limiting mechanism and an elastic reset mechanism forming a paper bin; the width limiting mechanism includes two limit baffles, two racks and a gear, the two limit baffles are relatively arranged in the paper bin shell, the gear is arranged between the two racks and meshes with the two, the two limit baffles are respectively connected to the two racks, the two limit baffles approach each other when the two racks move toward each other, and the two limit baffles move away from each other when the two racks move in opposite directions; the elastic reset mechanism acts on the racks to enable the two limit baffles to approach each other; wherein, a supporting plate is provided at the back of the paper bin shell, the two racks are movably arranged between the bottom wall of the paper bin shell and the supporting plate, and a movable guide mechanism is provided between the racks and the bottom wall and / or the supporting plate. The thermal printer of the utility model has the advantages of high reliability of the width limiting structure and high positioning accuracy of the paper roll in the paper bin shell.

Description

Technical Field

[0001] The present application relates to the technical field of printers, and in particular to a thermal printer. Background Art

[0002] Thermal printers can print on paper rolls (such as label paper rolls, ticket paper rolls, etc.). In order to adapt to paper rolls of different widths and prevent the paper roll in the paper bin from shifting during printing, a width limiting mechanism needs to be set to limit the axial position of the paper roll.

[0003] In some embodiments, the width limiting mechanism includes two limit baffles arranged relatively in the paper bin housing, the two limit baffles are connected to two racks respectively, a gear meshing with the two racks is arranged between the two racks, one longitudinal side of the rack forms a sliding fit with the paper bin housing, the two limit baffles move away from each other when the two racks move in opposite directions, and the two limit baffles approach each other when the two racks move toward each other, and the axial position of the paper roll is limited when the two limit baffles move to a close position abutting against the paper roll. Since the rack only forms a sliding fit with the paper bin housing at one longitudinal side, the problem that this width limiting mechanism is prone to is that the rack and the limit baffle are prone to shaking, which not only makes it easy for the limit baffle to get stuck or jammed during movement, resulting in poor movement stability, but also affects the precise positioning of the paper roll. Utility Model Content

[0004] In view of the deficiencies in the prior art, the main purpose of the utility model is to provide an improved thermal printer to improve the movement stability of the limit baffle and the positioning accuracy of the paper roll.

[0005] In order to achieve the above main purpose, the utility model provides a thermal printer, comprising:

[0006] A paper bin shell forming a paper bin;

[0007] The width limiting mechanism comprises two limit baffles, two racks and a gear; wherein the two limit baffles are arranged relatively in the paper bin housing, the gear is arranged between the two racks and meshes with the two racks, the two limit baffles are connected to the two racks respectively, when the two racks move towards each other, the two limit baffles approach each other, and when the two racks move away from each other, the two limit baffles move away from each other;

[0008] An elastic reset mechanism acts on the rack to enable the two limit baffles to approach each other;

[0009] Wherein, a supporting plate is provided on the back of the paper bin shell, the two racks are movably arranged between the bottom wall of the paper bin shell and the supporting plate, and a movable guiding mechanism is provided between the racks and the bottom wall and / or the supporting plate.

[0010] Furthermore, the movable guide mechanism includes a first movable guide portion arranged on the support plate and a second movable guide portion arranged on the rack, one of the first movable guide portion and the second movable guide portion is a guide groove, and the other of the first movable guide portion and the second movable guide portion is a guide rib cooperating with the guide groove.

[0011] Furthermore, the movable guide mechanism includes a third movable guide portion arranged on the bottom wall and a fourth movable guide portion arranged on the rack, one of the third movable guide portion and the fourth movable guide portion is a guide rib, and the other of the third movable guide portion and the fourth movable guide portion is a guide groove cooperating with the guide rib.

[0012] According to a specific embodiment of the utility model, two opposite end walls of the paper bin shell are provided with extension parts extending toward the back of the paper bin shell, and a snap fit is formed between the opposite ends of the support plate and the extension parts of the two opposite end walls.

[0013] In some embodiments, the elastic return mechanism includes an elastic return member acting on at least one of the racks.

[0014] Furthermore, one end of the elastic return member is connected to the rack, and the other end of the elastic return member is connected to the paper bin shell or the supporting plate.

[0015] In some embodiments, the elastic reset mechanism includes an elastic reset member, and two ends of the elastic reset member are respectively connected to the two racks.

[0016] Furthermore, the elastic return member is a spring.

[0017] According to a specific embodiment of the utility model, a mounting portion is provided at one end of the rack, the limit baffle has a connecting end connected to the mounting portion, and an avoidance groove for the connecting end to pass through and move is provided on the bottom wall of the paper bin shell.

[0018] According to a specific implementation of the utility model, a supporting protrusion is provided on the bottom wall of the paper bin shell, the gear is rotatably mounted on the supporting protrusion, and the supporting protrusion is provided with an elastic buckle to prevent the gear from falling off.

[0019] The technical solution of the utility model has the following beneficial effects:

[0020] During use, the user can move the two limit baffles to move them back to back and away from each other to facilitate the insertion of the paper roll; after the paper roll is inserted, as the user releases the limit baffles, the two racks can move toward each other under the action of the elastic reset mechanism, so that the two limit baffles approach each other until they abut against the two ends of the paper roll to achieve the positioning of the paper roll, which has the advantages of simple structure of the paper roll limit mechanism and easy operation.

[0021] Furthermore, two racks are movably arranged between the bottom wall of the paper bin shell and the supporting plate, and the supporting plate is used to support the rack as a whole, and a movable guide mechanism is provided between the rack and the bottom wall and / or the supporting plate, which is conducive to the smooth movement of the rack and the limit baffle, and prevents the rack and the limit baffle from shaking, so as to improve the positioning accuracy of the paper roll in the paper bin shell.

[0022] In order to more clearly illustrate the purpose, technical solutions and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a structural diagram of the thermal printer in Example 1 after removing the paper bin cover;

[0024] Figure 2 is a structural diagram showing the matching state between the paper roll and the limit baffle in Example 1;

[0025] Figure 3 is a structural diagram of the paper bin housing assembly in Example 1;

[0026] Figure 4 is a structural diagram of the paper bin housing assembly after the support plate is removed in Example 1;

[0027] Figure 5 It is a structural exploded view of the width limiting mechanism and the paper bin housing in Example 1;

[0028] Figure 6 is a diagram of the coordination structure of the width limiting mechanism and the supporting plate in Embodiment 1;

[0029] Figure 7 is a structural diagram of the limit baffle and the rack in Example 1;

[0030] Figure 8a is a diagram of the installation structure of the gear in Example 1;

[0031] Figure 8b is a state diagram of the gear in embodiment 1 when it is installed in place;

[0032] Fig. 9 This is a structural diagram of the paper bin shell assembly in Example 2 after removing the supporting plate and the elastic reset member. DETAILED DESCRIPTION

[0033] In the following description, many specific details are explained in combination with the embodiments to facilitate a full understanding of the present invention, but it should be understood that the following embodiments and detailed descriptions are only for illustrative purposes and do not limit the scope of protection of the present invention.

[0034] Example 1

[0035] like Figure 1-Figure 7 As shown, the thermal printer of the first embodiment includes a paper bin housing 10 and a width limiting mechanism 20, and a paper bin 10a for placing a paper roll is formed inside the paper bin housing 10. Figure 5 As shown, the width limiting mechanism 20 includes two limit baffles 21 , two racks 22 and a gear 23 ; wherein the two limit baffles 21 are respectively connected to the two racks 22 , and the gear 23 is disposed between the two racks 22 and meshes with the two racks 22 .

[0036] Combination Figures 3 to 5 As shown, a support plate 13 is provided on the back of the paper bin housing 10, and the support plate 13 is arranged opposite to the bottom wall 11 of the paper bin housing 10, and two racks 22 are movably arranged between the support plate 13 and the bottom wall 11. The gear 23 is preferably arranged at the axial center position of the paper bin housing 10. Specifically, as Figure 5 As shown, a supporting protrusion 113 is provided on the bottom wall 11 of the paper bin housing 10 , and the gear 23 is rotatably sleeved on the supporting protrusion 113 to simplify the installation structure of the gear 23 .

[0037] Preferably, combined Figure 8a and 8b As shown, the support protrusion 113 includes a support body 1131 and an elastic buckle 1132, the support body 1131 forms a rotational fit with the center hole 231 of the gear 23, the elastic buckle 1132 is arranged to pass through the center hole 231 of the gear 23, and the end of the elastic buckle 1132 is provided with an anti-dropout buckle portion 1133, and the anti-dropout buckle portion 1133 abuts against the end surface 232 of the gear 23 facing away from the bottom wall 11 to prevent the gear 23 from falling off the support protrusion 113. The number of the elastic buckles 1132 can be one or more, for example, two in the embodiment.

[0038] When assembling gear 23, Figure 8aAs shown, the center hole 231 of the gear 23 can be aligned with the supporting protrusion 113 and pressed. During the pressing process, when the anti-dropout buckle portion 1133 abuts against the gear 23, the elastic buckle 1132 can produce an overall elastic avoidance deformation, so that the anti-dropout buckle portion 1133 enters the center hole 231, allowing the gear 23 to be installed smoothly; after the gear 23 is installed in place, the elastic buckle 1132 is reset, and the anti-dropout buckle portion 1133 abuts against the end face 232 of the gear 23 to prevent the gear 23 from falling off the supporting protrusion 113. In the embodiment, the gear 23 is assembled by pressing, and no other fasteners are required, which has the advantages of simple structure and high assembly efficiency.

[0039] The two limit baffles 21 are relatively arranged in the paper bin 10a of the paper bin housing 10. The two can be symmetrically arranged relative to the axial center of the paper bin housing 10, and can approach or move away from each other as the two racks 22 move. Specifically, when the two racks 22 move toward each other, the two limit baffles 21 approach each other, and when the two racks 22 move away from each other, the two limit baffles 21 move away from each other. Among them, through the cooperation of the gear 23 and the rack 22, it can be ensured that the movement amount of the two limit baffles 21 is always the same, and then the paper roll can be accurately positioned in the center of the paper bin 10a.

[0040] Further, a moving guide mechanism is provided between the rack 22 and the bottom wall 11 and / or the supporting plate 13 to guide the movement of the rack 22. Preferably, a moving guide mechanism is provided between the rack 22 and the bottom wall 11 and the supporting plate 13.

[0041] The movable guide mechanism may include a first movable guide portion provided on the support plate 13 and a second movable guide portion provided on the rack 22, one of the first movable guide portion and the second movable guide portion is a guide groove, and the other of the first movable guide portion and the second movable guide portion is a guide rib matched with the guide groove. Figure 6 As shown, the support plate 13 is provided with a guide groove 131 extending along its longitudinal direction and serving as an example of a first movable guide portion, and the rack 22 is provided with a guide rib 223 cooperating with the guide groove 131 and serving as an example of a second movable guide portion.

[0042] Further, the movable guide mechanism may include a third movable guide portion provided on the bottom wall 11 and a fourth movable guide portion provided on the rack 22, one of the third movable guide portion and the fourth movable guide portion is a guide rib, and the other of the third movable guide portion and the fourth movable guide portion is a guide groove matched with the guide rib. Figure 5 As shown, the bottom wall 11 is provided with a guide rib 112 extending in the longitudinal direction thereof and serving as an example of a third movable guide portion, and the rack 22 is provided with a guide groove 225 cooperating with the guide rib 112 .

[0043] Combination Figure 3 and Figure 4 As shown, the two opposite end walls 12 of the paper bin housing 10 in the axial direction are provided with extensions 121 extending toward the back of the paper bin housing 10, and the opposite ends of the support plate 13 and the extensions 121 of the two opposite end walls 12 form a snap fit. Specifically, the extension 121 can be provided with a snap groove 122 (see Figure 4 ), the opposite ends of the support plate 13 may be provided with a clamping protrusion 132 (see Figure 6 ), the engaging protrusion 132 is inserted into the engaging groove 122 to fix the supporting plate 13 on the paper bin housing 11.

[0044] Optionally, the positions of the clamping protrusion 132 and the clamping slot 122 can be interchanged, that is, the clamping protrusion 132 can be set on the extension portion 121, and the clamping slot 122 can be set on the supporting plate 13. As a variation of the embodiment, the supporting plate 13 may not be fixed on the paper bin housing 10, but may be fixed inside the thermal printer in a manner independent of the paper bin housing 10.

[0045] Furthermore, the thermal printer of Embodiment 1 further comprises an elastic reset mechanism acting on the rack 22, so that the two limit baffles 21 can approach each other. Figure 4 As shown, the elastic reset mechanism in Embodiment 1 includes two elastic reset members 31, and the two elastic reset members 31 act on the two racks 22 respectively. The two elastic reset members 31 can apply pulling forces in opposite directions to the two racks 22 respectively to pull the two racks 22 to move toward each other, so that the two limit baffles 21 move in a direction close to each other to limit the paper roll.

[0046] The elastic reset member 31 is preferably a spring, one end of which is connected to the rack 22, and the other end is connected to the paper bin housing 10 or the supporting plate 13. Figure 4 As shown, the paper bin housing 10 is provided with a first hook portion 13, the rack 22 is provided with a second hook portion 224, and the two ends of the spring as an example of the elastic reset member 31 are respectively connected to the first hook portion 13 and the second hook portion 224. As a variation of Example 1, the elastic reset mechanism can be provided with only one elastic reset member 31, and the one elastic reset member 31 can act on any one of the two racks 22. When the one elastic reset member 31 pulls one of the racks 22, the other rack 22 can move toward each other through the transmission of the gear 23.

[0047] Furthermore, if Figure 7As shown, the rack 22 is generally L-shaped, including a rack portion 221 and a mounting portion 222, wherein the mounting portion 222 is located at one end of the rack 22. The limit baffle 21 has a connection end 211 connected to the mounting portion 222, and the connection end 211 can be fixedly connected to the mounting portion 222 by screws, or other connection methods such as snap-on connection can be used, and the present invention does not limit this. Figure 5 As shown, the bottom wall 11 of the paper bin housing 10 is provided with an escape groove 111 for the connection end 211 to pass through and move, and the two escape grooves 111 are symmetrically arranged relative to the axial center of the paper bin housing 10 .

[0048] In the present invention, the width limiting mechanism 20, the elastic reset mechanism and the supporting plate 13 can be assembled onto the paper bin housing 10 to obtain a paper bin housing assembly, and then the paper bin housing assembly can be installed as a whole into the outer shell of the thermal printer. When in use, the user can move the two limit baffles 22 to move them away from each other in order to facilitate the insertion of paper rolls; Figure 2 As shown, after the paper roll 100 is put in, as the user releases the limit baffle 22, the two racks can move toward each other under the action of the elastic reset mechanism, so that the two limit baffles 22 approach each other until they abut against the two ends of the paper roll 100 to achieve the positioning of the paper roll.

[0049] Example 2

[0050] The difference between Example 2 and Example 1 is that the elastic reset mechanism in Example 2 includes an elastic reset member such as a spring, both ends of which are respectively connected to the two racks 22, and can apply a pulling force to the two racks 22 to move the two racks 22 toward each other.

[0051] Specifically, Fig. 9 As shown, in Embodiment 2, the mounting portions 222 of the two racks 22 are each provided with a second hooking portion 224, and the two ends of the elastic reset member (not shown in the figure) are respectively connected to the second hooking portions 224 on the two racks 22. In this way, under the pulling force of the elastic reset member, the two racks 22 can move toward each other, so that the two limit baffles 21 move in a direction close to each other, so as to limit the paper roll.

[0052] Although the present invention is described above through embodiments, it should be understood that the above embodiments are only used to exemplarily describe the feasible implementation methods of the present invention, and should not be interpreted as limiting the scope of protection of the present invention. That is, any replacement or change made by those skilled in the art in accordance with the present invention should also be covered by the scope of protection of the claims of the present invention.

Claims

1. A thermal printer, comprising a paper bin housing forming a paper bin; characterized in that: The width limiting mechanism comprises two limit baffles, two racks and a gear; wherein the two limit baffles are arranged relatively in the paper bin housing, the gear is arranged between the two racks and meshes with the two racks, the two limit baffles are connected to the two racks respectively, when the two racks move towards each other, the two limit baffles approach each other, and when the two racks move away from each other, the two limit baffles move away from each other; An elastic reset mechanism acts on the rack to enable the two limit baffles to approach each other; Wherein, a supporting plate is provided on the back of the paper bin shell, the two racks are movably arranged between the bottom wall of the paper bin shell and the supporting plate, and a movable guiding mechanism is provided between the racks and the bottom wall and / or the supporting plate.

2. The thermal printer according to claim 1, characterized in that: The movable guide mechanism includes a first movable guide portion arranged on the support plate and a second movable guide portion arranged on the rack, one of the first movable guide portion and the second movable guide portion is a guide groove, and the other of the first movable guide portion and the second movable guide portion is a guide rib cooperating with the guide groove.

3. The thermal printer according to claim 1, characterized in that: The movable guide mechanism includes a third movable guide portion arranged on the bottom wall and a fourth movable guide portion arranged on the rack, one of the third movable guide portion and the fourth movable guide portion is a guide rib, and the other of the third movable guide portion and the fourth movable guide portion is a guide groove cooperating with the guide rib.

4. The thermal printer according to claim 1, characterized in that: The two opposite end walls of the paper bin shell are both provided with extension parts extending toward the back of the paper bin shell, and the opposite ends of the supporting plate form a snap fit with the extension parts of the two opposite end walls.

5. The thermal printer according to claim 1, characterized in that: The elastic reset mechanism comprises an elastic reset member acting on at least one of the racks.

6. The thermal printer according to claim 5, characterized in that: One end of the elastic reset member is connected to the rack, and the other end of the elastic reset member is connected to the paper bin shell or the supporting plate.

7. The thermal printer according to claim 1, characterized in that: The elastic reset mechanism comprises an elastic reset member, and two ends of the elastic reset member are respectively connected to the two racks.

8. The thermal printer according to any one of claims 5 to 7, characterized in that: The elastic reset member is a spring.

9. The thermal printer according to claim 1, characterized in that: A mounting portion is provided at one end of the rack, the limit baffle has a connecting end connected to the mounting portion, and an avoidance groove for the connecting end to pass through and move is provided on the bottom wall of the paper bin shell.

10. The thermal printer according to claim 1, characterized in that: A supporting convex portion is provided on the bottom wall of the paper bin shell, the gear is rotatably sleeved on the supporting convex portion, and the supporting convex portion is provided with an elastic buckle to prevent the gear from falling off.

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